Abstract

Background: The course of disease in COPD patients is difficult to predict. We hypothesized that the emphysema Index or visual emphysema assessment score could predict exacerbations and deterioration in PFTs the following year.

Methods: In this retrospective cohort study, we searched for COPD patients with at least one chest CT, detailed documentation of acute exacerbations the following year, and corresponding spirometry and clinical evaluation (mMRC, BODE, etc.) at the time of CT and a year after. Correlations between emphysema and the rate/severity of exacerbations, PFTs and clinical indices were evaluated.

Results: 54 patients were evaluated. Exacerbation rate was 1.72/year and hospitalization 1.07/year. Correlation was found between Emphysema Index and exacerbations requiring hospitalization, with an index of 20.2%±11.6 in patients with exacerbations but no hospitalizations and 10.6%±13.5 in patients hospitalized at least once (p=0.005). No other correlation was found between emphysema and exacerbations. Emphysema index had a negative correlation with FEV1FVC (PCC=-0.561, p=0.001), FEV1 (PCC=-0.415, p=0.011), GOLD grade (p=0.007) and BODE Index (PCC=0.045, p=0.04) that correlated also to the visual score (p<0.05). Emphysema Index was also a significant predictor of the degree of decline in FEV1 (PCC=-0.340, p=0.049), FVC (PCC=-0.398, p=0.029), and FEV1FVC (p<0.028).

Conclusions: Emphysema had no significant correlation with the rate of exacerbation except for lower emphysema levels in COPD patients hospitalized for exacerbation, suggesting that the rate/severity of exacerbations are not dependent on the level of emphysema. Emphysema was found to be a relatively good predictor of PFTs and their deterioration.